It has been 40 years since the overthrow of the Shah of Iran in a revolution that saw his rule replaced with the Islamic Republic.

On Talk to Al Jazeera, we speak to Kamal Kharazi, a former foreign minister, ambassador to the United Nations and a leading voice on the principles of the Islamic Republic. He was also a military spokesman during the Iran-Iraq War, with a central role in Iranian state media.

Kharazi is now chairman of Iran's Strategic Council for Foreign Relations and foreign policy adviser to the Supreme Leader, Ali Khamenei.

So, 40 years on, has the revolution achieved its goals of resisting Western interference and righting social injustices?

And how is Iran overcoming the challenges of the US withdrawal from the nuclear disarmament deal, the imposition of tougher sanctions, and heightened tensions in the region?

European countries should say why they're selling so many arms to Saudi Arabia and the United Arab Emirates and to Israel... while they are selling arms to these countries, Iran has the right to develop its own armaments, including missile technology.

Kamal Kharazi, former Iranian foreign minister

The US's withdrawal from the nuclear deal, or Joint Comprehensive Plan of Action (JCPOA), was the cause of much consternation, and a number of European signatory countries have vowed to work to keep it alive without the US. 

Kharazi says the success of those efforts relies ultimately on European nations and their willingness to act independently of Washington's threats of penalties and sanctions. 

However, even European partners who want to stay in the nuclear deal have raised concerns about Iran's ballistic missile programme - especially after a number of missile tests and the unveiling of the new Dezful ballistic missile - fears Kharazi says were unfounded. 

He adds that Iran has every right to enhance its defence strategy and that there was no truth in accusations that it was "destabilising the region".

"There are many enemies and they have all kinds of different armaments," says Kharazi. "Those who have developed terrorist groups and have tried to topple existing governments... those are the [some] bodies who have destabilised the region."

"We have tried to keep the status quo by fighting against terrorism in Iraq and Syria, which were defended by the help of Iran. Therefore, Iran has been a stabilising factor, not the destabilising factor," he continues. 

On the current relationship between Iran and the US and whether he sees a potential for improved dealings, Kharazi says this is in the hands of the US policymakers.

"There is animosity between Iran and the United States," says Kharazi. "They're using all their instruments to put pressure on Iran." 

"They have to change their policies. They have to come up with a new policy. Unfortunately, the United States is trying to materialise financial imperialism. If, in the past, imperialism was dependent on arms and wars, today Americans are dependent on financial instruments," Kharazi said. 

Closer to home, regional tensions were discussed. On the GCC blockade and how it affects his country, Kharazi said Iran is unhappy with the way the political impasse has progressed. 

"We are not happy that disputes are developing in the region," he said. "That does not help the development of security and peace in the region. We are ready to talk to everyone in the region, even Saudi Arabia, the United Arab Emirates... all other parties. And we believe, eventually, that is the final solution. Out of intervention of foreign countries. If we sit together and talk to each other for the benefit of the region, I believe something will come out of that." 

Asked if Iran had been able to reach the goals set forth by the Iranian Revolution 40 years ago, Kharazi says that, although not everything may have been achieved, great improvements have been made. 

"I don't think that all the aims of the revolution have been achieved, but there has been a great development in Iran," he said. "What is most important is that all of these [developments] have happened without the support of foreigners. It has been based on self-reliance, by the resources that we have internally. That is why Iran is inspiring." 

Source: Al Jazeera